INTRODUCTION
Tracker is a powerful desktop-neutral first class object database,
tag/metadata database, search tool and indexer.
Tracker is also extremely fast and super efficient with your systems memory
when compared with some other competing frameworks and is by far the fastest
and most memory efficient Nautilus search and Deskbar backends currently
availble.
It consists of a common object database that allows entities to have an almost
infinte number of properties, metadata (both embedded/harvested as well as
user definable), a comprehensive database of keywords/tags and links to other
entities.
It provides additional features for file based objects including context
linking and audit trails for a file object.
It has the ability to index, store, harvest metadata. retrieve and search all
types of files and other first class objects.
First class object support includes : Files, Documents, Music, Images, Videos,
Playlists*, Notes*, Applications*, Contacts*, Emails*, Conversations*,
Appointments*, Tasks*, Bookmarks*, History* and Projects*.
(* these services are not currently indexed at the moment but will be in later
versions)
All discussion related to tracker happens on the tracker mailing list
(http://mail.gnome.org/mailman/listinfo/tracker-list) and/or irc channel
#tracker on irc.gimp.net
More infomation on Tracker can be found at
http://tracker-project.org
USE CASES
Tracker is the most powerful open source metadata database and indexer
framework currently available and because it is built around a combination
indexer and sql database and not a dedicated indexer it has much more powerful
use cases:
* Provide search and indexing facilities similiar to those on other systems
* Common database storage for all first class objects (EG a common
music/photo/contacts/email/bookmarks/history database) complete with
additional metadata and tags/keywords
* Comprehensive one stop solution for all applications needing an object
database, powerful search (via RDF Query), first class methods, related
metadata and user definable metadata/tags
* Can provide a full semantic desktop with metadata everywhere
* Can provide powerful criteria based searching suitable for creating smart
file dialogs and vfolder systems
* Can provide a more intelligent desktop using statistical metadata
FEATURES
* Desktop-neutral design (its a freedesktop product built around other
freedesktop technologies like DBus and XDGMime but contains no GNOME
specific dependencies)
* Very memory efficient and non-leaking (typical RAM usage 4 - 30 MB). Unlike
some other indexers, tracker is designed and built to run well on lower
memory systems with typically 128MB or 256MB memory. It should even be
efficient enough to use on some mobile devices.
* Non-bloated and written in C for maximum efficiency.
* Small size and minimal dependencies makes it easy to bundle into various
distro's including live cds.
* Fast indexing and unobtrusive - no need to index stuff overnight. Tracker
runs at nice+10 so it should have a minimal impact on your system.
* Implements the freedesktop specification for metadata
(http://freedesktop.org/wiki/Standards/shared-filemetadata-spec)
* Extracts embedded File, Image, Document and Audio type metadata from files.
* Supports the WC3's RDF Query syntax for querying metadata
* Provides support for both free text search (like Beagle/Google) as well as
structured searches using RDF Query
* Respond in real time to file system changes to keep its metadata database up
to date and in synch
* Fully extendable with custom metadata - you can store, retrieve, register
and search via RDF Query all your own custom metadata
* Can extract a file's contents as plain text and index them
* Provides text filters for PDF, MS Office, OpenOffice (all versions), HTML
and PS files.
* Can provide thumbnailing on the fly
INSTALLATION (from source):
Run time dependencies (also needed for build) :
* Sqlite 3.2+ (Tracker source has an inlined version which is
statically-linked by default due to the lack of guarantee of threadsafety
in distro versions)
* libdbus (0.60 +)
* dbus-glib bindings (0.60 +)
* GLib (2.10)
* zlib
* intltool (>=0.3.5)
* GMime
Additional recommended packages:
* gstremer 0.10 + plugins for audio/video files to be indexed
* xsltproc
* w3m
* file
* wv (1.0.2+)
* poppler (pdftotext)
* libvorbis
* libpng
* libexif
* libgsf
* GTK and Gnome stack for GUI tools
* libglade (for tracker-preferences UI)
* unac (accent stripper)
* exempi
* libxml2
The following are necessary if Tracker's deskbar-handler is to be installed:
* python-dev (>= 2.3)
* python-gtk2-dev (>= 2.3)
* deskbar-applet (>= 2.14.2)
Optional run-time dependency:
* xdg-utils (provides some functionality needed by tracker-search-tool but falls
back to gnome-open if not available)
COMPILATION
To compile Tracker, use the following commands :
./configure --prefix=/usr --sysconfdir=/etc
make
sudo make install
If you install using any other prefix, you might have problems with files
not being installed correctly.
(You may need to copy and amend the dbus service file to the correct
directory and/or might need to update ld_conf if you install into non
standard directories.)
Notes to build tracker on Solaris
To compile Tracker with GCC on Solaris uses the following commands :
./configure --prefix=/usr --sysconfdir=/etc --with-pic CFLAGS=-D_POSIX_PTHREAD_SEMANTICS
make
(login as root)
make install
To compile Tracker with SUN Studio on Solaris uses the following commands,
because there are some problems to compile exiv2 using SUN C++ compiler:
./configure --prefix=/usr --sysconfdir=/etc --with-pic --disable-warnings \
--disable-exiv2 CFLAGS=-D_POSIX_PTHREAD_SEMANTICS
make
(login as root)
make install
Compile Options
Tracker has several compiler options to enable/disable certain features. The
following is available (all options should be passed as command line
parameters to autogen.sh (EG ./autogen.sh --disable-fam)
--enable-debug-code : build with debug symbols
--enable-video-extractor=(gstreamer, xine, external, auto)
--enable-file-monitoring=(inotify, fam, polling, auto)
--disable-preferences : disables the tracker-preferences capplet
--enable-deskbar-applet=(auto, handler, module) : enables support for
Deskbar-applet; 'auto' should do since it automatically chooses
whether to install the 'handler' (for Deskbar-applet >=2.14.2) or
the 'module' (for Deskbar-applet >=2.19)
--with-deskbar-applet-dir=(directory where Deskbar-applet should find
Tracker-handler; this should be automatically detected, perhaps in
/usr/lib/deskbar-applet/{handlers/modules-2.20-compatible})
--disable-gui : disables building of tracker-search-tool
--disable-pdf : disables the PDF data extractor
--disable-exif : disables the exif data extractor
--disable-libtrackergtk : disables the building of libtracker-gtk
--disable-gsf : disables the GSF data extractor
--disable-warnings : disables GCC warnings
--disable-unac : disables accent stripping
--disable-libxml2 : disables HTML/XML extractors (full-text will still be available)
--disable-xmp : disables XMP extraction
--with-session-bus-services-dir=(path to D-Bus services directory): this
should be automatically detected
--enable-external-qdbm : use system qdbm instead of one included in Tracker
--disable-hal : disables HAL support for ac power detection
--disable-trackerapplet : disables Tracker's notification applet
RUNNING TRACKER
To run Tracker, you need to manually start the Tracker daemon, trackerd. By
default trackerd will index your entire home directory.
You can also pass a directory root to be indexed as a command line parameter
if you dont want your entire home directory indexed. EG
"trackerd -i /home/jamie/Documents"
(if you want your home directory indexed when explicily specifying index
directory roots then you must add your home directory to the arguments:
EG trackerd -i /home/jamie -i /mnt/share)
You can disable indexing by passing --no-indexing
You can enable a low memory usage mode (recommended for machines with less
than 256MB of RAM) by passing --enable-low-memory
You can artificially throttle indexing by passing --throttle=value where value
is in the range 0-20 (with 0, the default, being fastest and 20 being slowest).
Default is 0. You should only change this value if you want to prevent noisy
fans or hot laptops arising from cpu intensive indexing. Tracker should have a
negligible impact on the system (as it is scheduled) so you can safely work
with it on full throttle without experiencing slow downs.
You can specify directory roots to be excluded from being watched or indexed
by passing -e directory for each directory root
You can specify logging verbosity by passing --verbosity. Valid values are
from 0 to 3, ranging from least to most verbose respectively.
Yet another option is --language which allows for specifying the language to
use for stemmer and stop-words list.
All the above options (and more) can be set by editing ~/.config/tracker.cfg
which is created with specific defaults when non-existent (EG when
trackerd is ran for the first time). Ensure that you restart trackerd for the
changes to take effect. tracker.cfg also provides options that allows tracker
to only index a subset of your home directory as well as other folders not
in your home directory by setting WatchDirectoryRoots to a semicolon-delimited
list of directories (full path required!)
EG:
WatchDirectoryRoots=directory1;directory2;directory3
An additional option, introduced during the 0.6 development cycle, is the
--reindex option which indexes user data from scratch, removing the need to
remove Tracker database manually.
On the first run, Tracker will automatically create a new database and start
populating it with metadata by browsing through the user's home directory (or
the root folder(s) specified).
On subsequent runs, Tracker will start up much much faster and will only ever
incrementally index files (IE files that have changed since last index).
If installed correctly, the Tracker daemon (trackerd) can also be started
automatically via Dbus activation (EG by running tracker-search SEARCHTERM)
Settig Inotify Watch Limit
When watching large numbers of folders, its ppossible to exceed the default number
of inotify watches. In order to get real time updates when this value is exceeded
it is necessary to increase the number of allowed watches. This can be done as
follows:
1) Add this line to /etc/sysctl.conf:
"fs.inotify.max_user_watches = (number of folders to be watched; default is 8192)"
2) Reboot the system
Tracker And Nautilus Search
Once you have installed Tracker and have some indexed contents, you should now
compile Nautilus (ver 2.13.4 or higher) which should auto-detect that Tracker
is installed and automatically compile in Tracker support. You are now ready
to appreciate a powerful and super efficient C-based indexer in all its
glory... happy hunting!
To make sure trackerd always start when you login to Gnome, you will need to
add it to Gnome-session (select sessions from preferences menu, select startup
program tab and then add /usr/bin/trackerd). For non-gnome installations, see
the desktop docs for how to auto start an application for your particular
desktop.
Tracker and Deskbar applet
Tracker is also integrated in GNOME's deskbar applet. Please see that applet
for more info.
TRACKER TOOLS
Tracker comes with a number of command line apps that you can use:
"tracker-tag" for setting and searching tags/keywords
"tracker-stats" - this displays the current number of indexed items by category
"tracker-extract FILE" - this extracts embedded metadata from FILE and prints
to stdout
"tracker-search SEARCHTERM" - this perfoms a google like search using
SEARCHTERM to retrieve all matching files where SEARCHTERM appears in any
searchable metadata
"tracker-query" - this reads an RDF Query that specifies the search criteria
for various fields. It prints to STDOUT all matching files. You can see some
example queries in the RDF-Query-examples folder. You can run the examples as
"tracker-query < RDFFILE"
"tracker-status" - queries status of trackerd
"tracker-preferences" - GUI tool to set Tracker preferences
"tracker-applet" - Tracker notification applet which, other than showing the
current status of Tracker, also has facilities such as searching, pausing
indexing, showing statistics, and launching both TST and tracker-preferences
